1. Field of the Invention
The present invention relates to a reformer for a fuel cell and more particularly to a plate type reformer for a fuel cell.
2. Description of the Related Art
As is well known, a fuel cell is an electricity generating system that generates electrical energy through an electrochemical reaction between oxygen and hydrogen contained in hydrocarbon materials such as methanol, ethanol, or natural gas.
A polymer electrolyte membrane fuel cell (hereinafter, referred to as PEMFC) has been recently developed. The PEMFC has excellent output characteristics, a low operating temperature, and fast starting and response characteristics. Therefore, the PEMFC has a wide range of applications including as a mobile power source for vehicles, as a distributed power source for homes or other buildings, and as a small-size power source for electronic apparatuses.
A fuel cell system employing the PEMFC scheme includes a stack, a reformer, a fuel tank, and a fuel pump. The stack constitutes an electricity generator set having a plurality of unit cells (or electricity generators), and the fuel pump supplies fuel stored in the fuel tank to the reformer. Then, the reformer reforms the fuel to generate hydrogen gas (or hydrogen-rich reformed gas) and supplies the hydrogen gas to the stack.
In more detail, the reformer generates the hydrogen gas from the fuel through a chemical catalytic reaction using thermal energy. That is, the reformer includes a heat source part for generating the thermal energy, a reforming reaction part for generating reformed gas containing hydrogen from the fuel by using the thermal energy, and a carbon-monoxide reducing part for reducing the concentration of carbon monoxide contained in the reformed gas.
In the reformer of the conventional fuel cell system, the heat source part, the reforming reaction part, and the carbon-monoxide reducing part are formed in a vessel shape and are separately distributed from each other and connected to each other through pipes. Because of this, heat cannot be directly exchanged between the respective parts, thereby causing an inefficiency from the viewpoint of heat delivery. In addition, since the respective parts are separately distributed, the entire fuel cell system cannot be compactly embodied.